Liquid-level gauge for gasoline tanks



Feb. 22 1927. 1,618,442

K. H. KIEF ER LIQUID LEVEL GAUGE FOR GISOLINE TANKS Filed Aug/26, 1924 PatentedFeb. 22, 1927.

v UNITED STATES PATENT OFFICE.

KENNETH HALL KIEFER, or BALTIMORE,

MA YLAND, assrenon or onn-ronn'rn TO SIDNEY G. VINCENT AND ONE-FOURTH TO FREDERICK G. VOLKMAN, OF BALTI- MORE, MARYLAND.

LIQUID-LEVEL GAUGE FOR GASOLINE TANKS.

Application filed August 26, 1924. Serial No. 734,303.-

.This invention relates. to liquid level gauges, and has special reference to a gauge for use in connection with gasoline tanks of automobiles.

One of the objects or" the invention is to improve on the gauge shown and described in my copending application for patent on gasoline gauges, filed August 11, 1923, Serial Number 656,829.

In the gauge described in the aforesaid application, there is employed a pressure tube extending vertically from the top to the bottom of the tank. Thetube in question is substantially filled with air and communicates by a capillary tube with an indicator arranged on the dash of the automobile, whereas in the present invention, the tube is virtually or substantially filled with gasoline, which at no time during the operation of the device voluntarily drains from the tube, thus a medium is held in the tube that is not so susceptible to the various changes in temperature, as air, and consequently thev possibility of inaccurate readings is reduced to a minimum.

A further object of the invention isto prevent surges due to the movement of the contents of the tank, and in this connection the invention contemplates the provision of the tube with means to steadythe level of 4 gasoline in the'tube, and prevents it from being surged or splashed into the capillary tube.

The invention further contemplates a novel construction for the bottom of the gasoline tube wherein the gasoline in they tube is guarded against surges due to vibration of the car, and at the same time permits the gasoline to pass from the tank into the tube to fill it tothe desired point, while also aiding to some extent in maintaining the column of gasoline in the tube. under the vacuum pressure or suction at all times except when the device is operated .to let the gas out of the tube. A. still further and important object of the invention is to improve theform and arrangement of thega'soline tube, and the method of operation with this pressure tube is thatit will at all times be practically filled with gasoline, and thus the difliculties due to thepressure of a large volume of air will i be eliminated, thereby minim1zingtemper-- ature changes, the .method of operation largely controlling this desirable result.

While it has been stated that the invention has certain primary and important objects, I contemplate another object and advantage incident to the construction about to be described, and that is that the gasoline tube within the tank may serve in an emergency as a reserve or emergency gasoline supply.

In the drawings illustrating the invention Fig. l is a general schematic view of an apparatus for carrying out the invention. 7 Fig. 2 is an'enlarged section of the gasoline tube, capillary tube, and a part of the gasoline tank.

Fig. 3 is a sectional view of a tank showing the tank substantially filled'with thegas line near the top, and showing'in a diagramunits of the bellows diaphragm compressed or contracted, from normal position, the gasoline line. in the gasoline tube being shown at substantiallylthe same point as it occupied when the tank was full.

Fig. '5 is a view showing a modified form of a cover or closure for the gasoline tube.

--Relierrir1g to the drawings, the numeral 1 designates a gasoline tank provided with the usual filling orifice 2. This tank has attached thereto an elbow 3, to which is connected by a union 4, a capillary tube 5 which extends to the dash 6 of an automobile. There is shown upon this dash an indicator 7, and there is also shown the bellows dia.'

phragm 8, which at the outset it will be said, may be enclosed in any suitable casing forminga part of the indicator or otherwise, and so arranged that its expansion and contraction will, through. suitable mechanism communicating the reciprocatory movement of the diaphragm, and convert that movement it necessary, to a suitable dial or indicator readily visible from the drivers seat. V

The elbow 3 is provided with a nipple 9 threaded internally torthe reception of a vent plug 10, the purpose of which will presently be described. This elbow at its ill] Then the plug 10 is reinserted.

lower end is threaded into a boss 11 of the top 12 oil the gasoline tube 13. This top is preferably provided with a flange 14. which overlies slightly the annular flange 15 of a rim 1o soldered or otherwise attached to the upper side of the tank 1, as shown best in Fig. Over the top of the cover 12 is placed an annulus 17 threaded to the rim is, as indicated at 18. The tube contains near its top a conical ballle 19 provided with a central orilice 20. This ballie prevents surges of gasoline to the top off the tube, and thereby prevents "asoline from passing into the capillary system.

Threaded into the bottom of the tube is a ring 21, having a comparatively large central opening covered by a disk of memhraneous material 1??) or material that will allow gasoline to pass through, but not air when used under crmditions present in the gauge, Iin'eierably chaniois. which material by experiment, I have found admirably adapted to my purpose. This dish is held to the ring by a metallic annulus or ring 524i, and may he so held by the screws shown, or by any other convenient means.

As shown in Fig. a, there is a rack 26 indicated. llIOWQVGl, it will he understood, as before intimated, that in this ligure, both the dia iihragm and the rack are in practice ren'iote from the tank, and the rack may be an element cooperating with suitable gears and pinions of an indicator mechanism, to indicate to the driver the level of the gasoline in the tank.

1t is my purpose to reduce the air space in the top of the gasoline tube to the miri the gasoline tube is fitted with a cap 28 provided with the central opening 29, and in this constructirm the inenibraneous disk 23 is held to the cap by screws 30 passing through a ring 31.

In operation, the vent plug 10 is removed and the tank 1 tilled to its regular capacity. Under these conditions, not only will the tank be filled to the top, but the gasoline will rise in the tube 13 to the same level.

The indicator mechanism is then adjusted to the point on the dial or drum, as the case may be, so as to indicate the quantity in gallons ol" gasoline in the tank. Next, this ineehaiiisn'i is locked in adjusted position. With the tank and tube thus arranged, any decrease in the quantity of fluid. in tank 1 Will tend to lower the level of the liquid in the gasoline tube 13, but since this tube does not con'nniiniicate freely with the air, in fact, the Whole system being hermetically sealed, the change in level in the tube will be C0111- paratively slight. However, with the proper positioning of the indicating instrument at the outset, the suction produced in this manncr Will show by the position oil? the indicator the quantity of gasoline remaining in the tank. The relative positions of the gas oline in the tank and in the gasoline tube are somewhat as ilulicated in lligs. 3 and i. It 110W all. of the gasoline be used out of the tank except that which is in the tube, the gasoline in the tube will not llOW out because of the *aouum or suction conditions that prevail, which Will maintain the column in the gasoline tube regardless of the level of the gas in the tank. These variations of suction pressure or vacuum, expand and contract according to the stages of the operations, the diaphragm 8, and there being attached to the trout of the diaphragm a rod having connection With the indicator mechanism, the "tll'ltllZ-lOI'lS of compressioir or contraction and en iansion ol? the units of the bellows, will be communicated to the indicator mechanism. This mechanism may be substantially as shown in my copending application referred to hereinbefore, but since no claim herein is made to any particular indicator mechanism, it has not been deemed necessary to illustrate such a mechanism, tor obviously those skilled in the art will readily perceive the mode of operation.

De )endin to some extent u )011 the size.

oi. the tank and the size ot the gasoline tube, the gasoline tube may he resorted to in an emergency for an additional small amount of gasoline. In order, however, that the supply in the tube may become available, it will, of course, be necessary to vent the sys tem by removal of the plug 10 when conditions of atmospheric pressure will prevail throughout the systen'i, and all of the gasoline contained in the gasoline tube will flow out of the opening in the bottom thereof into the tank, from which place it is conveyed in the usual manner to theengine.

The term pressure here used means in:

the present case, a suction pressure, and is used in the absence of a better and more accurate term, but as explained hereinbetore, it is the suction .in the capillary system due to the varying level of the gasoline in the gasoline tube, that is depended upon in the main for actuating the bellows diaphragm through suitable lii'uichanism to indicate the gasoline level in the tank. Obviously, after the first lilling o't' thetank, it is not necessary or desirable to vent the system upon future fillings, and as before intimated, this vent-i ing ofthe system is only necessary upon the first filling, or in case that the gasoline in the gasoline tube is desired as an emergency supply.

Claims.

1. In a liquid level gauge, the combination with a liquid tank, of a tube extending into said tank from the top to a point adjacent the bottom thereof, and having an opening in its lower end, a pressure responsive indicator, a liquid-free capillary tube connecting said indicator with the first mentioned tube, both of said tubes being hermetically sealed I from the atmosphere when the tank is emptying, and means for temporarily venting the first mentioned tube so that the 'tank and tube, in the first instance, can be filled to the same level under atmospheric pressure, the closing of said vent permitting the emptying of the tank without substantially lowering the level of the liquid in the said first mentioned tube, whereby, as the level of the liquid falls in the tank, the indicator will be operated continuously, through the capillary tube, to indicate the quantity of the liquid in the tank. 2. In a liquid level gauge, the combinatio with a liquid tank, of a gasoline tube extending vertically from the top to a point adjacent the bottom thereof, and having an opening in its lower end closed by a member of Inembraneous material designed to permit passage of the gasoline between the tube and tank to change the height of-the liquid in said tube, a vacuum responsive indicator, a liquid-free capillary tube connecting the indicator with the first men tioned tube, wherethrough the indicator is operated, upon the variation of the height of the liquid in the gasoline tube, and means for temporarily venting said gasoline tube closed by a member of membraneous material designed to permit passage of the gasoline between the tube and tank to change the height of the liquid in the tube, a pressure responsive indicator, a liquid-free capillary tube connecting the indicator with the first mentioned tube, wherethrough the indicator is operated upon the variation of the height of the liquid in the gasoline tube, and means for temporarily venting said gasoline tube when the tank is being filled, in the first instance, to permit said tube and tank to be filled simultaneously under atmospheric pressure.

4c. The method of installing a fluid pressure actuated gauge including a liquid tube having at its upper end a closable vent to the atmosphere and a capillary connection to a pressure responsive gauge, which meth od consists in placing the liquid tube in a vessel, filling the vessel and tube simultaneously, under atmospheric pressure while the vent of the tube is open, and then closing the vent whereby the gauge is adapted to be operated continuously thereafter.

In testimony whereof I afiix my signature.

'KENNETH HALL KIEFER. 

